The boxes where you edit your regular expressions, replacement strings, and test subjects are full-featured edit controls. In fact, they are the same edit control that powers EditPad, one of the most flexible and convenient text editors available today (see http://www.editpadpro.com).
Beyond typing in text, the editor box recognizes the following keyboard shortcuts:
Arrow key Moves the text cursor (blinking vertical bar).
Ctrl+Left arrow Moves the text cursor to the start of the previous word or the end of the previous line, whichever is closer.
Ctrl+Right arrow Moves the text cursor to the start of the next line or the end of the current line, whichever is closer.
Page up/down Moves the text cursor up or down an entire screen.
Ctrl+Page up/down Scrolls the text one screen up or down.
Home Moves the text cursor to the beginning of the line.
Ctrl+Home Moves the text cursor to the start of the entire text.
End Moves the text cursor to the end of the line.
Ctrl+End Moves the text cursor to the end of the entire text.
Shift+Movement key Moves the text cursor and expand or shrink the selection towards the new text cursor position.
If there was no selection, one is started.
Pressing Ctrl as well, will move the text cursor correspondingly.
Ctrl+] Moves the text cursor to the bracket that matches the bracket the cursor is presently at.
Ctrl+[ Selects the text between the innermost pair of brackets that surround the text cursor.
Repeat the command to select the brackets too.
Repeat again to select the text between the next level of brackets.
Enter Inserts a line break.
Ctrl+Enter Inserts a page break
Delete Deletes the current selection if there is one and selections are not persistent.
Otherwise, the character to the right of the caret is deleted.
Ctrl+Delete Deletes the current selection if there is one.
Otherwise, the part of the current word to the right of the text cursor is deleted.
Shift+Ctrl+Delete All the text on the current line to the right of the text cursor is deleted.
Backspace Deletes the current selection if there.
Otherwise, the character to the left of the text cursor is deleted.
Ctrl+Backspace Deletes the current selection if there.
Otherwise, the part of the current word to the left of the text cursor is deleted.
Shift+Ctrl+Backspace Deletes the current selection if there is one.
Otherwise, all the text on the current line to the left of the text cursor is deleted.
Alt+Backspace Undo
Alt+Shift+Backspace Redo
Ctrl+Z Undo
Ctrl+Y Redo
Insert Toggles between insert and overwrite mode.
Tab If there is a selection, the entire selection is indented.
Otherwise, a tab is inserted.
Shift+Tab If there is a selection, the entire selection is unindented (outdented).
Otherwise, if there is a tab, or a series of spaces the size of a tab, to the left of the text cursor, that tab or spaces are deleted.
Ctrl+A Select All
Ctrl+Alt+Y Delete Line
Shift+Ctrl+Alt+Y Duplicate Line
Ctrl+X Cut
Ctrl+C Copy
Ctrl+V Paste
Shift+Delete Cut
Ctrl+Insert Copy
Shift+Insert Paste